xi. CETEOSAURUS HABITS OF LIFE. 291 



for determining its characters, the title of Oxoniensis ; and as a 

 convenient, if temporary, device, to call the animal with longer 

 caudal vertebrae Glymptonensis, from the name of the place which 

 has yielded the most characteristic series of these bones. This may 

 possibly be equivalent to C. longus, though of earlier date. 



The vertebral column of ceteosaurus of which the characters 

 have now been traced oifers subjects for grave reflection in re- 

 ference to the affinities of deinosaurian and crocodilian reptiles. 

 A lizard of such vast proportions would seem to claim easy ad- 

 mission to the deinosaurians, and to take its place naturally with 

 megalosaurus or iguanodon, if not with both those its great con- 

 temporaries. But its fore-limbs are more crocodilian, its pelvic 

 girdle more lacertian, while its vertebral system is of a peculiar 

 type, anomalous even in the club-headed neural spine, and singular 

 in the change from opisthocselian through amphicselian to what 

 occasionally approaches to procselian structure. 



These vertebrse vary in length in some regular order ; increasing 

 in the dorsal series from the forward to the backward bones ; greatly 

 diminished, probably in the later lumbar, certainly in the broad 

 first caudals, after which they are again lengthened to about the 

 middle of the tail, and then suffer gradual abbreviation. A down- 

 ward curvature in some instances appears in the two or three of 

 the last caudals. * 



The avian affinity so conspicuous in megalosaurus is absent here ; 

 in the shortness of the tibiae some analogy appears to hyla3osaurus 

 and scelidosaurus ; in the convexo-concave anterior dorsals it agrees 

 with streptospondylus ; the limbs are on the whole more crocodilian, 

 except that the hind-foot may have been tridactyle; the pectoral 

 and pelvic arches more Varanian. 



Was the dermal surface of this animal loricate, or protected by 

 scuta like those of the crocodile ; or squamate, as in many reptiles ; 

 or approximately smooth, as in the enaliosaurians ? Not loricate, 

 if we may trust the negative evidence obtained at every place yet 

 found to yield bones of ceteosaurus, the same places often yielding 

 scuta of teleosaurus, or steneosaurus. Was the ridge of the back 

 or the tail carinated or crested, as in the monitors and iguanians, with 

 dermal spines or vertical scales ? No answer can be given ; analogy 

 indeed may be appealed to in favour of this view, which is in 

 harmony with what has been observed in the deinosaurian races 



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